The Ohio Secretary of State’s web page has this list of presidential primary candidates, and also an explanation that Bill Weld was removed from the Republican ballot, and John Delaney was removed from the Democratic ballot, because of paperwork errors. The Ohio Secretary of State had previously removed Andrew Yang from the Democratic ballot for paperwork errors.
In no other state have so many major party presidential candidates approved by their parties been kept off the ballot.
The Ohio Republican presidential primary ballot will only list President Donald Trump. The Democratic ballot will list eleven candidates: Bennet, Biden, Bloomberg, Booker, Buttigieg, Gabbard, Klobuchar, Patrick, Sanders, Steyer, and Warren.